Manufacture of artificial filaments



Patented Sept. 10, 1935 UNITED STATES PATENT I OFFICE burg, Arnhem,

Netherlands, assignors, by

mesne assignments, to American Enka 'Corporation, Wilmington, Delaware Del., a corporation of No Drawing. Application December 2, 1932, Serial No. 645,416. In Germany June 24, 1932 4 Claims.

Our present invention relates to a new method for producing filaments, threads and the like having a matt appearance or dull lustre from cellulosic solutions, especially from viscose or from cuprammonium cellulose solutions.

The adding of mixtures of non-volatile or difficultly volatile organic or inorganic substances and easily volatile organic substances to spinning solutions in order to produce artificial silk of reduced lustre is already known.

We have found that advantageous effects can be attained if tin oxide (SnOz) in combination with volatile organic substances is incorporated in a spinning solution, such as viscose or cuprammonium solution. As examples of volatile organic substances, which we preferably use, may be mentioned hydroaromatic cyclic oxycompounds, such as cyclo-hexanol (hexahydrophenol Cal-InOI-I), methylcyclohexanol (hexahydrocresol C1H14O) or alicyclic alcohols of the group comprising fenchyl alcohol, terpenehydrate, terpineol, which may be used in the form of pine oil; but it should be understood that other easily volatile organic substances may be used.

The mixture to be added to the spinning solution according to the present invention has an exceptionally good covering power, so that degrees of mattness to the most varied extent can be achieved easily and even without large quantities of the solid substance, which otherwise adversely affects the resistance and structure, being necessary to be used. It is usually possible to manage with approximately 1% of tin oxide calculated on the artificial silk substance if the volatile additional substance be suitably selected. The pigment tin oxide is completely white.

In cases where viscose is used as a spinning solution a certain browning of the spun material can occur owing to the hydrogen sulphide developed in spinning and in the subsequent treatment on account of the partial formation of brown tin sulphide. This may occur especially in using precipitated tin oxide.

We have found that this evil can be avoided, if tin oxide, manufactured in a special manner, be used. It was particularly found that the tin oxide SnOz produced by direct burning of the tin in oxygen is kept entirely inert in the viscose and remains in a surprising manner quite white even in the treatment in the viscose process. The size of the particles of the tin oxide thus produced is very fine, so that a grinding is in many cases superfluous and the manufactured product can be mixed with the volatile organic additional substance by rubbing in without further treatment, and then can be emulsified or stirred in the spinning material, for example the viscose.

Example a smaller or larger quantity of pine oil and the paste then thoroughly stirred in the rest of the pine oil and the preparation thus produced is then emulsified in the viscose.

Having thus described our invention, what we claim is:

1. A spinning solution for the manufacture of soft-lustre, cellulosic products comprising a solution of the group consisting of viscose and cuprammonium cellulose, burnt tin oxide and a highly volatile, organic liquid.

2. A spinning solution for the manufacture of soft-lustre, cellulosic products comprising a solution of the group consisting of viscose and cuprammonium cellulose, burnt tin oxide and a volatile liquid of the group consisting of hydroxyaromatic cyclic oxy-compounds, fenchyl alcohol, terpenehydrate, and pine oil.

3. A viscose spinning solution for the manufacture of soft-lustre, cellulosic products comprising approximately 10 kilograms of viscose, 7 per cent alkali, 8 grams of burnt tin oxide and grams of pine oil.

4. A soft-lustre, cellulosic product containing burnt tin oxide.

THEODOOR KOCH.

JOI-IANNES GERARDUS WEELDENBURG. 

